Down Syndrome Flashcards
How is Down Syndrome inherited? Name 3 possible mechanisms.
- Sporadic in 95% cases dt nondisjunction in meiosis
- Unbalanced translocation between chromosome 21 and another acrocentric chromosome (usually chromosome 14) in 3-4%, 75% de novo, rest familial (balanced parental Robertsonian translocation- papa less risk of passing on)
- Mosaicism- 1-2%, some normal cells, some affected, more overall mild phenotype
How effective is first trimester screening for Down syndrome?
2nd trimister?
Combined?
- 1st trimester 85%
- 2nd trimester 80%
- Combined 95%
What is a risk factor for Down syndrome?
Advanced maternal age ( :( My ovaries…)
Name 11! Facial/Physical Features of Down Syndrome
- Small brachycephalic head (broad width head)
- Epicanthal fold (skin fold of the upper eyelid covering the inner corner of the eye)
- Flat nasal bridge
- Upward slanting palpebral fissures
- Small mouth
- Large protruding tongue
- Small ears
- Increased thickness of nuchal fold (in utero)
- Single transverse palmar crease
- Short 5th finger with clinodactyly (bent)
- Sandal toe deformity
- Late fontanelle closure
Name 1 cognitive feature associated with Down Syndrome
- Variable, mild to severe developmental delay
Name 4 ENT Features of Down Syndrome
- Serous otitis media (50-70%)
- Hearing loss (75%)
- OSA (50-80%)
- Noisy breathing
Name 5 eye features seen in Down Syndrome
- Brushfield spots
- Cataracts (15%)
- Severe refractive errors (50%)
- Strabismus
- Glaucoma
Name 5 Congenital Heart defects associated with Down Syndrome
- AVSD
- VSD
- Tetralogy of Fallot
- ASD
- PDA
Name 5 hematologic conditions children with Down Syndrome are at increased risk for
- Transient myeloproliferative disorder (10%), regress spontaneously in the first 3 mos of life, later risk of leukemia is however 10-30% in these children.
- Polycythemia
- Leukemia (1%) both ALL and AML- specific subtype of AML called AMKL (acute megakaryoblastic leukemia)
- Macrocytosis
- Iron deficiency anemia w macrocytosis NOT microcytic
Name 7 GI conditions children w Down Syndrome are at increased risk for.
- Intestinal atresia (12%)
- Anorectal stenosis or atresia
- Hirschprungs disease
- Constipation
- GERD
- Celiac disease
Name 4 neurologic conditions children with Down Syndrome are at increased risk for
- Hypotonia
- Infantile spasms
- Seizures
- Alzheimer’s after age 40
Name 2 MSK conditions DS children are at risk for
- Congenital hip dislocation
2. Atlanto-axial instability
Name 3 endocrine conditions children with DS are at increased risk for
- Hypothyroidism (both congenital and later onset)
- DM
- Obesity
How do we diagnose Down Syndrome postnatally?
- Physical exam is the most sensitive in the first 24h of life
- FISH- can detect extra copy, but cannot detect translocations
- Complete chromosome analysis (karyotype)
How do we detect Down Syndrome prenatally?
- Low AFP
- Low estriol
- High BHCG
- Increased nuchal fold thickness
- Short femur length
Name 7 tests babies with DS should have done at birth
- Chromosomal analysis to confirm dx
- Echocardiogram
- CBC
- TSH
- Hearing test
- Eye exam (red reflex)
- Swallowing assessment IF feeding difficulties
Name 5 pieces of anticipatory guidance that should be given to parents of newborns with DS
- Increased susceptibility to resp infxns
- Feeding issues, constipation
- Cervical spine positioning precautions
- Support in community, resources, early intervention services
- Review genetics, risk in subsequent pregnancies
Name 4 evaluations/tests that should be done for children with DS from 1 mo-1yo
- Hearing test at 6 mos
- Optho referral w/in first 6 mos
- TSH at 6 and 12 months
- Hemoglobin at 12 mos
Name 5 pieces of anticipatory guidance for children w DS that should be discussed btw 1 mo-1yo
- Risk of otitis media
- Feeding issues, constipation
- Symptoms of OSA
- Review cervical spine positioning precautions
- Early intervention services-referral
What are 3 investigations that are NOT routinely recommended in children with DS
- Renal US
- Cervical Xrays
- DS Growth charts
Name 5 tests/investigations that should be done for children w DS btw 1yo-5yo
- Behavioural audiogram and tympanometry every 6 mos until bilateral ear specific testing possible, then behavioral audiogram annually.
- Ophthalmology annually
- Sleep study by 4yo
- Hemoglobin annually
- TSH annually
Name 4 pieces of anticipatory guidance that should be reviewed for children with DS btw 1yo-5yo
- Review risk of otitis media
- Review sx of OSA, myelopathy, hypothyroidism, celiac dz
- Delayed tooth eruption/hypodentition
- Risk of obesity-diet/activity counselling
Name 4 tests that should be done for children 5+yo w DS
- Ophthalmology q2yrs, then q3yrs after age 13
- Behavioral audiogram annually
- TSH annually
- Hemoglobin annually
Name 6 pieces of anticipatory guidance for children w DS aged 5+
- Review sx of OSA, myelopathy, hypothyroidism, celiac dz, skin issues
- Risk of contact sports, trampolines
- Transition to school-IEP
- Monitor for behavioral proble,s -ADHD, OCD
- Puberty, BCP when appropriate
- Transition to adulthood when appropriate (grp homes etc.)
